Image release to be used by major photographic industry advertising agency

Adidas can run a promotion by giving away free footballs, but a photographer cannot run a promotion by giving away free photos?
Strange way to approach business.
Advertising costs can be either: income paid out of cash reserves (to someone else), or a lack of income on something you have created. Seems fair to me.
The only question is: is an amateur allowed to do the same thing?

Adidas can run a promotion by giving away free footballs, but a photographer cannot run a promotion by giving away free photos?
Strange way to approach business.

Advertising costs can be either: income paid out of cash reserves (to someone else), or a lack of income on something you have created. Seems fair to me.
The only question is: is an amateur allowed to do the same thing?